Just fill your rad up, let it sit for 5-10 minutes. Plug the holes with your thumbs or plugs( its up to you) and shake the crap out of it for a few minutes. Then i usually drain it into a clear plastic or glass bowl to see what kind of nastiness comes out with the clr. If its really dirty do a quick rinse with tap water and repeat step one. Then i fill and shake with tap water 3 or 4 times or until theres no more bubbles coming out. Finally i fill and drain it with distilled to clear it of tap water. I lean the rad against something with the ports facing down with paper towel under it and let it drain completely and dry. Or you can bypass this and plug it back into your loop.
You can use clr with gaskets and acrylic it wont hurt either. I take the tops off of my cpu and gpu blocks fill them with clr for a few minutes and check to see if theres anything left behind. If not i rinse with tap water and hand dry them. If there is crap still inside the blocks i gently brush with an old toothbrush and a little clr. If that doesnt get rid of it you can try soaking it for 20 or 30 minutes but usually if it hasnt come off with the toothbrush its not coming off with anything. I have soaked a couple really bad blocks overnight and managed to get almost all of the crud to come off of copper blocks. I would be really careful with nickel plated blocks doing this, as well as scrubbing them very much being that most plating is very very thin. If theres a tiny hole you can inadvertently make it far bigger by brushing or scrubbing to hard. With nickel prevention is the best route.
Is that CLR -> pour in, plug holes with G 1/4 end caps, shake for 5-10 min, drain rad (what to drain with??) and then you are ready to go?? Do you just place CPU/GPU blocks in a cup with it, minus the gaskets of course??? Don't use on acrylic??
